A powerful collection of poems revolving round the mining communities of the South Wales valleys, focusing on two pits in particular: Cwm-Cynon Pit (Cynon Pit) which, in 1950, was one of the first pits to close after over a century of production; and the Senghenydd Pit, in 1913 the scene of a terrible explosion in which over four hundred men and boys died, after which it never re-opened.

D M Thomas writes: "A few tin-mines in Cornwall are being re-opened by international combines. The shaft is the poem is one and many, like the persona: who is variously a foreign mining engineer, myself, my father, dead miners related to me."